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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/cpu/cpufreq/longhaul.c
downloadlwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/i386/kernel/cpu/cpufreq/longhaul.c')
-rw-r--r--arch/i386/kernel/cpu/cpufreq/longhaul.c658
1 files changed, 658 insertions, 0 deletions
diff --git a/arch/i386/kernel/cpu/cpufreq/longhaul.c b/arch/i386/kernel/cpu/cpufreq/longhaul.c
new file mode 100644
index 000000000000..ab0f9f5aac11
--- /dev/null
+++ b/arch/i386/kernel/cpu/cpufreq/longhaul.c
@@ -0,0 +1,658 @@
+/*
+ * (C) 2001-2004 Dave Jones. <davej@codemonkey.org.uk>
+ * (C) 2002 Padraig Brady. <padraig@antefacto.com>
+ *
+ * Licensed under the terms of the GNU GPL License version 2.
+ * Based upon datasheets & sample CPUs kindly provided by VIA.
+ *
+ * VIA have currently 3 different versions of Longhaul.
+ * Version 1 (Longhaul) uses the BCR2 MSR at 0x1147.
+ * It is present only in Samuel 1 (C5A), Samuel 2 (C5B) stepping 0.
+ * Version 2 of longhaul is the same as v1, but adds voltage scaling.
+ * Present in Samuel 2 (steppings 1-7 only) (C5B), and Ezra (C5C)
+ * voltage scaling support has currently been disabled in this driver
+ * until we have code that gets it right.
+ * Version 3 of longhaul got renamed to Powersaver and redesigned
+ * to use the POWERSAVER MSR at 0x110a.
+ * It is present in Ezra-T (C5M), Nehemiah (C5X) and above.
+ * It's pretty much the same feature wise to longhaul v2, though
+ * there is provision for scaling FSB too, but this doesn't work
+ * too well in practice so we don't even try to use this.
+ *
+ * BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous*
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/cpufreq.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include <asm/msr.h>
+#include <asm/timex.h>
+#include <asm/io.h>
+
+#include "longhaul.h"
+
+#define PFX "longhaul: "
+
+#define TYPE_LONGHAUL_V1 1
+#define TYPE_LONGHAUL_V2 2
+#define TYPE_POWERSAVER 3
+
+#define CPU_SAMUEL 1
+#define CPU_SAMUEL2 2
+#define CPU_EZRA 3
+#define CPU_EZRA_T 4
+#define CPU_NEHEMIAH 5
+
+static int cpu_model;
+static unsigned int numscales=16, numvscales;
+static unsigned int fsb;
+static int minvid, maxvid;
+static unsigned int minmult, maxmult;
+static int can_scale_voltage;
+static int vrmrev;
+
+/* Module parameters */
+static int dont_scale_voltage;
+
+
+#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "longhaul", msg)
+
+
+#define __hlt() __asm__ __volatile__("hlt": : :"memory")
+
+/* Clock ratios multiplied by 10 */
+static int clock_ratio[32];
+static int eblcr_table[32];
+static int voltage_table[32];
+static unsigned int highest_speed, lowest_speed; /* kHz */
+static int longhaul_version;
+static struct cpufreq_frequency_table *longhaul_table;
+
+#ifdef CONFIG_CPU_FREQ_DEBUG
+static char speedbuffer[8];
+
+static char *print_speed(int speed)
+{
+ if (speed > 1000) {
+ if (speed%1000 == 0)
+ sprintf (speedbuffer, "%dGHz", speed/1000);
+ else
+ sprintf (speedbuffer, "%d.%dGHz", speed/1000, (speed%1000)/100);
+ } else
+ sprintf (speedbuffer, "%dMHz", speed);
+
+ return speedbuffer;
+}
+#endif
+
+
+static unsigned int calc_speed(int mult)
+{
+ int khz;
+ khz = (mult/10)*fsb;
+ if (mult%10)
+ khz += fsb/2;
+ khz *= 1000;
+ return khz;
+}
+
+
+static int longhaul_get_cpu_mult(void)
+{
+ unsigned long invalue=0,lo, hi;
+
+ rdmsr (MSR_IA32_EBL_CR_POWERON, lo, hi);
+ invalue = (lo & (1<<22|1<<23|1<<24|1<<25)) >>22;
+ if (longhaul_version==TYPE_LONGHAUL_V2 || longhaul_version==TYPE_POWERSAVER) {
+ if (lo & (1<<27))
+ invalue+=16;
+ }
+ return eblcr_table[invalue];
+}
+
+
+static void do_powersaver(union msr_longhaul *longhaul,
+ unsigned int clock_ratio_index)
+{
+ int version;
+
+ switch (cpu_model) {
+ case CPU_EZRA_T:
+ version = 3;
+ break;
+ case CPU_NEHEMIAH:
+ version = 0xf;
+ break;
+ default:
+ return;
+ }
+
+ rdmsrl(MSR_VIA_LONGHAUL, longhaul->val);
+ longhaul->bits.SoftBusRatio = clock_ratio_index & 0xf;
+ longhaul->bits.SoftBusRatio4 = (clock_ratio_index & 0x10) >> 4;
+ longhaul->bits.EnableSoftBusRatio = 1;
+ longhaul->bits.RevisionKey = 0;
+ local_irq_disable();
+ wrmsrl(MSR_VIA_LONGHAUL, longhaul->val);
+ local_irq_enable();
+ __hlt();
+
+ rdmsrl(MSR_VIA_LONGHAUL, longhaul->val);
+ longhaul->bits.EnableSoftBusRatio = 0;
+ longhaul->bits.RevisionKey = version;
+ local_irq_disable();
+ wrmsrl(MSR_VIA_LONGHAUL, longhaul->val);
+ local_irq_enable();
+}
+
+/**
+ * longhaul_set_cpu_frequency()
+ * @clock_ratio_index : bitpattern of the new multiplier.
+ *
+ * Sets a new clock ratio.
+ */
+
+static void longhaul_setstate(unsigned int clock_ratio_index)
+{
+ int speed, mult;
+ struct cpufreq_freqs freqs;
+ union msr_longhaul longhaul;
+ union msr_bcr2 bcr2;
+ static unsigned int old_ratio=-1;
+
+ if (old_ratio == clock_ratio_index)
+ return;
+ old_ratio = clock_ratio_index;
+
+ mult = clock_ratio[clock_ratio_index];
+ if (mult == -1)
+ return;
+
+ speed = calc_speed(mult);
+ if ((speed > highest_speed) || (speed < lowest_speed))
+ return;
+
+ freqs.old = calc_speed(longhaul_get_cpu_mult());
+ freqs.new = speed;
+ freqs.cpu = 0; /* longhaul.c is UP only driver */
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+ dprintk ("Setting to FSB:%dMHz Mult:%d.%dx (%s)\n",
+ fsb, mult/10, mult%10, print_speed(speed/1000));
+
+ switch (longhaul_version) {
+
+ /*
+ * Longhaul v1. (Samuel[C5A] and Samuel2 stepping 0[C5B])
+ * Software controlled multipliers only.
+ *
+ * *NB* Until we get voltage scaling working v1 & v2 are the same code.
+ * Longhaul v2 appears in Samuel2 Steppings 1->7 [C5b] and Ezra [C5C]
+ */
+ case TYPE_LONGHAUL_V1:
+ case TYPE_LONGHAUL_V2:
+ rdmsrl (MSR_VIA_BCR2, bcr2.val);
+ /* Enable software clock multiplier */
+ bcr2.bits.ESOFTBF = 1;
+ bcr2.bits.CLOCKMUL = clock_ratio_index;
+ local_irq_disable();
+ wrmsrl (MSR_VIA_BCR2, bcr2.val);
+ local_irq_enable();
+
+ __hlt();
+
+ /* Disable software clock multiplier */
+ rdmsrl (MSR_VIA_BCR2, bcr2.val);
+ bcr2.bits.ESOFTBF = 0;
+ local_irq_disable();
+ wrmsrl (MSR_VIA_BCR2, bcr2.val);
+ local_irq_enable();
+ break;
+
+ /*
+ * Longhaul v3 (aka Powersaver). (Ezra-T [C5M] & Nehemiah [C5N])
+ * We can scale voltage with this too, but that's currently
+ * disabled until we come up with a decent 'match freq to voltage'
+ * algorithm.
+ * When we add voltage scaling, we will also need to do the
+ * voltage/freq setting in order depending on the direction
+ * of scaling (like we do in powernow-k7.c)
+ * Nehemiah can do FSB scaling too, but this has never been proven
+ * to work in practice.
+ */
+ case TYPE_POWERSAVER:
+ do_powersaver(&longhaul, clock_ratio_index);
+ break;
+ }
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+}
+
+/*
+ * Centaur decided to make life a little more tricky.
+ * Only longhaul v1 is allowed to read EBLCR BSEL[0:1].
+ * Samuel2 and above have to try and guess what the FSB is.
+ * We do this by assuming we booted at maximum multiplier, and interpolate
+ * between that value multiplied by possible FSBs and cpu_mhz which
+ * was calculated at boot time. Really ugly, but no other way to do this.
+ */
+
+#define ROUNDING 0xf
+
+static int _guess(int guess)
+{
+ int target;
+
+ target = ((maxmult/10)*guess);
+ if (maxmult%10 != 0)
+ target += (guess/2);
+ target += ROUNDING/2;
+ target &= ~ROUNDING;
+ return target;
+}
+
+
+static int guess_fsb(void)
+{
+ int speed = (cpu_khz/1000);
+ int i;
+ int speeds[3] = { 66, 100, 133 };
+
+ speed += ROUNDING/2;
+ speed &= ~ROUNDING;
+
+ for (i=0; i<3; i++) {
+ if (_guess(speeds[i]) == speed)
+ return speeds[i];
+ }
+ return 0;
+}
+
+
+static int __init longhaul_get_ranges(void)
+{
+ unsigned long invalue;
+ unsigned int multipliers[32]= {
+ 50,30,40,100,55,35,45,95,90,70,80,60,120,75,85,65,
+ -1,110,120,-1,135,115,125,105,130,150,160,140,-1,155,-1,145 };
+ unsigned int j, k = 0;
+ union msr_longhaul longhaul;
+ unsigned long lo, hi;
+ unsigned int eblcr_fsb_table_v1[] = { 66, 133, 100, -1 };
+ unsigned int eblcr_fsb_table_v2[] = { 133, 100, -1, 66 };
+
+ switch (longhaul_version) {
+ case TYPE_LONGHAUL_V1:
+ case TYPE_LONGHAUL_V2:
+ /* Ugh, Longhaul v1 didn't have the min/max MSRs.
+ Assume min=3.0x & max = whatever we booted at. */
+ minmult = 30;
+ maxmult = longhaul_get_cpu_mult();
+ rdmsr (MSR_IA32_EBL_CR_POWERON, lo, hi);
+ invalue = (lo & (1<<18|1<<19)) >>18;
+ if (cpu_model==CPU_SAMUEL || cpu_model==CPU_SAMUEL2)
+ fsb = eblcr_fsb_table_v1[invalue];
+ else
+ fsb = guess_fsb();
+ break;
+
+ case TYPE_POWERSAVER:
+ /* Ezra-T */
+ if (cpu_model==CPU_EZRA_T) {
+ rdmsrl (MSR_VIA_LONGHAUL, longhaul.val);
+ invalue = longhaul.bits.MaxMHzBR;
+ if (longhaul.bits.MaxMHzBR4)
+ invalue += 16;
+ maxmult=multipliers[invalue];
+
+ invalue = longhaul.bits.MinMHzBR;
+ if (longhaul.bits.MinMHzBR4 == 1)
+ minmult = 30;
+ else
+ minmult = multipliers[invalue];
+ fsb = eblcr_fsb_table_v2[longhaul.bits.MaxMHzFSB];
+ break;
+ }
+
+ /* Nehemiah */
+ if (cpu_model==CPU_NEHEMIAH) {
+ rdmsrl (MSR_VIA_LONGHAUL, longhaul.val);
+
+ /*
+ * TODO: This code works, but raises a lot of questions.
+ * - Some Nehemiah's seem to have broken Min/MaxMHzBR's.
+ * We get around this by using a hardcoded multiplier of 4.0x
+ * for the minimimum speed, and the speed we booted up at for the max.
+ * This is done in longhaul_get_cpu_mult() by reading the EBLCR register.
+ * - According to some VIA documentation EBLCR is only
+ * in pre-Nehemiah C3s. How this still works is a mystery.
+ * We're possibly using something undocumented and unsupported,
+ * But it works, so we don't grumble.
+ */
+ minmult=40;
+ maxmult=longhaul_get_cpu_mult();
+
+ /* Starting with the 1.2GHz parts, theres a 200MHz bus. */
+ if ((cpu_khz/1000) > 1200)
+ fsb = 200;
+ else
+ fsb = eblcr_fsb_table_v2[longhaul.bits.MaxMHzFSB];
+ break;
+ }
+ }
+
+ dprintk ("MinMult:%d.%dx MaxMult:%d.%dx\n",
+ minmult/10, minmult%10, maxmult/10, maxmult%10);
+
+ if (fsb == -1) {
+ printk (KERN_INFO PFX "Invalid (reserved) FSB!\n");
+ return -EINVAL;
+ }
+
+ highest_speed = calc_speed(maxmult);
+ lowest_speed = calc_speed(minmult);
+ dprintk ("FSB:%dMHz Lowest speed: %s Highest speed:%s\n", fsb,
+ print_speed(lowest_speed/1000),
+ print_speed(highest_speed/1000));
+
+ if (lowest_speed == highest_speed) {
+ printk (KERN_INFO PFX "highestspeed == lowest, aborting.\n");
+ return -EINVAL;
+ }
+ if (lowest_speed > highest_speed) {
+ printk (KERN_INFO PFX "nonsense! lowest (%d > %d) !\n",
+ lowest_speed, highest_speed);
+ return -EINVAL;
+ }
+
+ longhaul_table = kmalloc((numscales + 1) * sizeof(struct cpufreq_frequency_table), GFP_KERNEL);
+ if(!longhaul_table)
+ return -ENOMEM;
+
+ for (j=0; j < numscales; j++) {
+ unsigned int ratio;
+ ratio = clock_ratio[j];
+ if (ratio == -1)
+ continue;
+ if (ratio > maxmult || ratio < minmult)
+ continue;
+ longhaul_table[k].frequency = calc_speed(ratio);
+ longhaul_table[k].index = j;
+ k++;
+ }
+
+ longhaul_table[k].frequency = CPUFREQ_TABLE_END;
+ if (!k) {
+ kfree (longhaul_table);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+
+static void __init longhaul_setup_voltagescaling(void)
+{
+ union msr_longhaul longhaul;
+
+ rdmsrl (MSR_VIA_LONGHAUL, longhaul.val);
+
+ if (!(longhaul.bits.RevisionID & 1))
+ return;
+
+ minvid = longhaul.bits.MinimumVID;
+ maxvid = longhaul.bits.MaximumVID;
+ vrmrev = longhaul.bits.VRMRev;
+
+ if (minvid == 0 || maxvid == 0) {
+ printk (KERN_INFO PFX "Bogus values Min:%d.%03d Max:%d.%03d. "
+ "Voltage scaling disabled.\n",
+ minvid/1000, minvid%1000, maxvid/1000, maxvid%1000);
+ return;
+ }
+
+ if (minvid == maxvid) {
+ printk (KERN_INFO PFX "Claims to support voltage scaling but min & max are "
+ "both %d.%03d. Voltage scaling disabled\n",
+ maxvid/1000, maxvid%1000);
+ return;
+ }
+
+ if (vrmrev==0) {
+ dprintk ("VRM 8.5 \n");
+ memcpy (voltage_table, vrm85scales, sizeof(voltage_table));
+ numvscales = (voltage_table[maxvid]-voltage_table[minvid])/25;
+ } else {
+ dprintk ("Mobile VRM \n");
+ memcpy (voltage_table, mobilevrmscales, sizeof(voltage_table));
+ numvscales = (voltage_table[maxvid]-voltage_table[minvid])/5;
+ }
+
+ /* Current voltage isn't readable at first, so we need to
+ set it to a known value. The spec says to use maxvid */
+ longhaul.bits.RevisionKey = longhaul.bits.RevisionID; /* FIXME: This is bad. */
+ longhaul.bits.EnableSoftVID = 1;
+ longhaul.bits.SoftVID = maxvid;
+ wrmsrl (MSR_VIA_LONGHAUL, longhaul.val);
+
+ minvid = voltage_table[minvid];
+ maxvid = voltage_table[maxvid];
+
+ dprintk ("Min VID=%d.%03d Max VID=%d.%03d, %d possible voltage scales\n",
+ maxvid/1000, maxvid%1000, minvid/1000, minvid%1000, numvscales);
+
+ can_scale_voltage = 1;
+}
+
+
+static int longhaul_verify(struct cpufreq_policy *policy)
+{
+ return cpufreq_frequency_table_verify(policy, longhaul_table);
+}
+
+
+static int longhaul_target(struct cpufreq_policy *policy,
+ unsigned int target_freq, unsigned int relation)
+{
+ unsigned int table_index = 0;
+ unsigned int new_clock_ratio = 0;
+
+ if (cpufreq_frequency_table_target(policy, longhaul_table, target_freq, relation, &table_index))
+ return -EINVAL;
+
+ new_clock_ratio = longhaul_table[table_index].index & 0xFF;
+
+ longhaul_setstate(new_clock_ratio);
+
+ return 0;
+}
+
+
+static unsigned int longhaul_get(unsigned int cpu)
+{
+ if (cpu)
+ return 0;
+ return calc_speed(longhaul_get_cpu_mult());
+}
+
+
+static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
+{
+ struct cpuinfo_x86 *c = cpu_data;
+ char *cpuname=NULL;
+ int ret;
+
+ switch (c->x86_model) {
+ case 6:
+ cpu_model = CPU_SAMUEL;
+ cpuname = "C3 'Samuel' [C5A]";
+ longhaul_version = TYPE_LONGHAUL_V1;
+ memcpy (clock_ratio, samuel1_clock_ratio, sizeof(samuel1_clock_ratio));
+ memcpy (eblcr_table, samuel1_eblcr, sizeof(samuel1_eblcr));
+ break;
+
+ case 7:
+ longhaul_version = TYPE_LONGHAUL_V1;
+ switch (c->x86_mask) {
+ case 0:
+ cpu_model = CPU_SAMUEL2;
+ cpuname = "C3 'Samuel 2' [C5B]";
+ /* Note, this is not a typo, early Samuel2's had Samuel1 ratios. */
+ memcpy (clock_ratio, samuel1_clock_ratio, sizeof(samuel1_clock_ratio));
+ memcpy (eblcr_table, samuel2_eblcr, sizeof(samuel2_eblcr));
+ break;
+ case 1 ... 15:
+ if (c->x86_mask < 8) {
+ cpu_model = CPU_SAMUEL2;
+ cpuname = "C3 'Samuel 2' [C5B]";
+ } else {
+ cpu_model = CPU_EZRA;
+ cpuname = "C3 'Ezra' [C5C]";
+ }
+ memcpy (clock_ratio, ezra_clock_ratio, sizeof(ezra_clock_ratio));
+ memcpy (eblcr_table, ezra_eblcr, sizeof(ezra_eblcr));
+ break;
+ }
+ break;
+
+ case 8:
+ cpu_model = CPU_EZRA_T;
+ cpuname = "C3 'Ezra-T' [C5M]";
+ longhaul_version = TYPE_POWERSAVER;
+ numscales=32;
+ memcpy (clock_ratio, ezrat_clock_ratio, sizeof(ezrat_clock_ratio));
+ memcpy (eblcr_table, ezrat_eblcr, sizeof(ezrat_eblcr));
+ break;
+
+ case 9:
+ cpu_model = CPU_NEHEMIAH;
+ longhaul_version = TYPE_POWERSAVER;
+ numscales=32;
+ switch (c->x86_mask) {
+ case 0 ... 1:
+ cpuname = "C3 'Nehemiah A' [C5N]";
+ memcpy (clock_ratio, nehemiah_a_clock_ratio, sizeof(nehemiah_a_clock_ratio));
+ memcpy (eblcr_table, nehemiah_a_eblcr, sizeof(nehemiah_a_eblcr));
+ break;
+ case 2 ... 4:
+ cpuname = "C3 'Nehemiah B' [C5N]";
+ memcpy (clock_ratio, nehemiah_b_clock_ratio, sizeof(nehemiah_b_clock_ratio));
+ memcpy (eblcr_table, nehemiah_b_eblcr, sizeof(nehemiah_b_eblcr));
+ break;
+ case 5 ... 15:
+ cpuname = "C3 'Nehemiah C' [C5N]";
+ memcpy (clock_ratio, nehemiah_c_clock_ratio, sizeof(nehemiah_c_clock_ratio));
+ memcpy (eblcr_table, nehemiah_c_eblcr, sizeof(nehemiah_c_eblcr));
+ break;
+ }
+ break;
+
+ default:
+ cpuname = "Unknown";
+ break;
+ }
+
+ printk (KERN_INFO PFX "VIA %s CPU detected. ", cpuname);
+ switch (longhaul_version) {
+ case TYPE_LONGHAUL_V1:
+ case TYPE_LONGHAUL_V2:
+ printk ("Longhaul v%d supported.\n", longhaul_version);
+ break;
+ case TYPE_POWERSAVER:
+ printk ("Powersaver supported.\n");
+ break;
+ };
+
+ ret = longhaul_get_ranges();
+ if (ret != 0)
+ return ret;
+
+ if ((longhaul_version==TYPE_LONGHAUL_V2 || longhaul_version==TYPE_POWERSAVER) &&
+ (dont_scale_voltage==0))
+ longhaul_setup_voltagescaling();
+
+ policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
+ policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
+ policy->cur = calc_speed(longhaul_get_cpu_mult());
+
+ ret = cpufreq_frequency_table_cpuinfo(policy, longhaul_table);
+ if (ret)
+ return ret;
+
+ cpufreq_frequency_table_get_attr(longhaul_table, policy->cpu);
+
+ return 0;
+}
+
+static int __devexit longhaul_cpu_exit(struct cpufreq_policy *policy)
+{
+ cpufreq_frequency_table_put_attr(policy->cpu);
+ return 0;
+}
+
+static struct freq_attr* longhaul_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+static struct cpufreq_driver longhaul_driver = {
+ .verify = longhaul_verify,
+ .target = longhaul_target,
+ .get = longhaul_get,
+ .init = longhaul_cpu_init,
+ .exit = __devexit_p(longhaul_cpu_exit),
+ .name = "longhaul",
+ .owner = THIS_MODULE,
+ .attr = longhaul_attr,
+};
+
+
+static int __init longhaul_init(void)
+{
+ struct cpuinfo_x86 *c = cpu_data;
+
+ if (c->x86_vendor != X86_VENDOR_CENTAUR || c->x86 != 6)
+ return -ENODEV;
+
+ switch (c->x86_model) {
+ case 6 ... 9:
+ return cpufreq_register_driver(&longhaul_driver);
+ default:
+ printk (KERN_INFO PFX "Unknown VIA CPU. Contact davej@codemonkey.org.uk\n");
+ }
+
+ return -ENODEV;
+}
+
+
+static void __exit longhaul_exit(void)
+{
+ int i=0;
+
+ for (i=0; i < numscales; i++) {
+ if (clock_ratio[i] == maxmult) {
+ longhaul_setstate(i);
+ break;
+ }
+ }
+
+ cpufreq_unregister_driver(&longhaul_driver);
+ kfree(longhaul_table);
+}
+
+module_param (dont_scale_voltage, int, 0644);
+MODULE_PARM_DESC(dont_scale_voltage, "Don't scale voltage of processor");
+
+MODULE_AUTHOR ("Dave Jones <davej@codemonkey.org.uk>");
+MODULE_DESCRIPTION ("Longhaul driver for VIA Cyrix processors.");
+MODULE_LICENSE ("GPL");
+
+module_init(longhaul_init);
+module_exit(longhaul_exit);
+